Okay, this is a new problem for me. Long story short, my 98 Durango keeps overheating. Took it to my mechanic who parked it in the back of his shop and ran it for about an hour, and it never overheated. Couldn't figure it out. Now that I've been doing alot of driving this past few weeks, I've discovered she overheats while in drive, almost red lining if I let it. But, as soon as I put it in park, she starts cooling down (takes about 10 minutes). That's why it wouldn't overheat for my mechanic, in park, it won't overheat. Operation of the Air Conditioning system has no bearing on whether or not she overheats. As soon as I put it in park, even with the Air Conditioner going, she starts cooling back down.

Anyone else ever heard of this? Any tips?

Thanks....

 

FS:
Sounds like your cooling system has enough capacity to cool things at idle, but not when the engine is doing any work. When was the last time your coolng system had a flush and refill?? I would suspect either a partially clogged radiator, or maybe a slowly dying water pump impeller.

Worst case would be a leaking head gasket allowing combustion gasses to enter the cooling system and really heat things up.

You might try driving around a bit with the windows down with the heater on full blast and see if that cools things down at all. If so,I would look closely at the radiator.

Don

 

Don, thanks for the help! I'll look into all the above. You've got me curious about the head gasket. I'm noticing just a bit of accelleration loss when going up hills, etc.

I'm also going to take it in for a flush asap.

I greatly appreciate your attention!

John

 

At 9+ years old, the stat and the radiator are probably simply due to be replaced. Start with a good flush of the system (careful with the heater core... you need to bypass that for the flush) and if that doesn't help, it's a parts replacement time. '98/'99s didn't have the extra cooling of the electic fan like the others did so they ran a little hot anyways.

When you replace your fluids after the flush or after the repair, use Prestone 50/50 premix AND a bottle of Redline's Water Wetter.

IndyDurango